JP2007319899A - Die forging method and forging die - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a forging die, whose structure is simple and which easily and surely positions a billet, and a die forging method using the same. <P>SOLUTION: The forging die comprises a flattening die 1 for flattening a billet W1, a roughing die 2 for preliminarily forming the flattened billet W1 into a rough shape material, and a finishing die for finishing the rough shape material into a prescribed shape. The flattening die 1 is provided with a positioning-shape forming part 15 for forming positioning-shapes W1a, by which the billet 1 is positioned relative to the roughing die 2, in the billet W1. The positioning shapes W1a of the billet W1 are engaged with portions 22 projecting from the roughing die 2, so that the billet W1 is positioned to a proper position on the roughing die 2. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a die forging method and a forging die, and in particular, a crushing process for flatly crushing a billet, a rough ground process for preliminarily forming a crushed billet with a rough ground mold, and a rough shaped material. A die forging and forming method for performing a finishing process to finish a predetermined shape with a mold, a crushing mold for flatly crushing a billet, a rough ground mold for preliminarily forming a crushed billet into a rough material, and a rough material The present invention relates to a forging die provided with a finishing die finished to a predetermined shape.

  For example, when hot forging a solid deformed part with a non-circular cross section or non-axis target, such as a steering knuckle, a crankshaft, or a connecting rod, which is one of automotive parts, generally refer to FIG. As described above, a rod-like or linear material is cut into an appropriate length (S1) to form a billet, and after heating this billet (S2), a crushing step of crushing the billet flatly with a crushing mold is performed ( S3) A rough ground process is performed in which a rough shaped material having a shape corresponding to a finished shape is preformed from the flatly crushed billet (S4), and a finishing process is performed in which the rough shaped material is finish-molded into a predetermined shape with a finishing die. (S5) A trimming process for removing burrs is performed (S6), and an inspection is finally performed (S7). In the conventional technique, generally, the billet W1 shown in FIG. 4A is crushed between the upper mold 10 ′ and the lower mold 11 ′ of the crushing mold 1 ′ as shown in FIG. As shown in FIG. 4 (c), it is positioned on the lower mold 21 'of the wasteland mold 2' and preformed with the upper mold 20 '. Further, in the finishing mold, similarly to the rough ground mold 2 ', the rough shape material is positioned and finish molding is performed.

  Forging dies such as the conventional wasteland mold 2 ′ and finishing dies for performing each step, positioning parts (for example, refer to Patent Document 1) for positioning the billet W1 and the rough profile in the longitudinal direction, A holding part is provided for holding the billet and the rough shape member so that they do not roll or shift in the mold and are positioned in the radial direction. In the lower mold 21 ′ of the wasteland mold 2 ′ shown in FIG. 4C and FIGS. 5 to 7, the longitudinal end portion of the impression so that the positioning portion 30 engages with the end surface W <b> 1 b of the billet W <b> 1. Alternatively, it is formed in a wall shape in the vicinity thereof, and the holding portion 31 is formed in a groove shape at a position where the billet W1 is placed.

  Further, as another conventional technique for holding the billet so as not to deviate from the set position of the forging die, in a forging die for manufacturing a forged product such as a turbine blade, a pair of die bodies are brought close to each other. A forging die characterized in that it is provided so as to be separable and a fixing means for restraining the forging material loaded between the die bodies is provided on the side of the die bodies so as to be able to advance and retreat. (Patent Document 2).

JP 2004-130347 A Japanese Utility Model Publication No. 05-39734

  However, in the above prior art, as shown in FIG. 4C and FIGS. 5 to 7, the positioning for contacting the end face W <b> 1 b of the billet W <b> 1 and the rough shape member (hereinafter referred to as billet 31). In the forging die provided with the portion 30, the position of the positioning portion 30 is limited to the end portion of the impression or the vicinity thereof. On the other hand, the billet W1 and the like need to be long enough to be fully filled in the impression of the forging die. Therefore, since the billet W1 and the like need to be long enough to be brought into contact with the positioning portion 30, the billet W1 and the like must be made longer than necessary, resulting in waste of materials and improving the yield. There was a problem that it was difficult. Further, even in the forging die provided with the groove-shaped holding portion 31, since the material such as the billet W1 is taken for the groove-shaped holding portion 31, the diameter of the billet W1 must be increased more than necessary. Therefore, there was a problem that the material was wasted and it was difficult to improve the yield. Further, in the positioning part 30 and the holding part 31 of the forging die, since the material such as the billet W1 flows most, the part wears quickly, and the die cannot be positioned accurately and the die life is short. There was also a problem.

  Further, among the above conventional techniques, in Patent Document 2, since the fixing means is provided separately from the molds provided so as to be close to and away from each other, the structure is complicated and the control is only complicated. In addition, there is a problem that it is difficult to actually restrain the forging material surely because it is necessary to pull out a fixing tool for restraining the forging material from between the die bodies when closing the die body.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a die forging method and a forging die that can easily and reliably position a billet or the like with a simple configuration.

In order to achieve the above object, the invention related to the die forging method according to claim 1 includes a crushing step for flatly crushing the billet, and a rough ground step for preliminarily forming the crushed billet with a rough die to form a rough shape, A die forging method that performs a finishing process of finishing a rough shape into a predetermined shape with a finishing die, and forming a positioning shape that can be positioned with respect to the next die in the previous step into a billet or a rough shape. It is characterized by doing.
In order to achieve the above object, the invention according to claim 2 provides a crushing mold for flatly crushing the billet, a rough ground mold for preliminarily forming the crushed billet to form a rough shape, and a rough shape material. A forging die having a finishing shape for finishing into a shape, and a positioning shape forming portion for forming a positioning shape which can be positioned with respect to a die in the next process into a billet or a rough shape material is provided in the mold in the previous process It is characterized by that.

According to the first aspect of the present invention, a positioning shape that can be positioned with respect to the waste mold in the crushing process is formed into a billet, and / or a positioning shape that can be positioned with respect to the finishing mold is formed into a rough material in the roughing process. Thus, there is provided a die forging method capable of easily and reliably positioning a billet and / or a rough profile with an appropriate volume of material.
In the invention of claim 2, the crushing die is provided with a positioning shape forming portion for forming a positioning shape that can be positioned with respect to the rough ground die into the billet, and / or the positioning that can be positioned with respect to the finishing die in the waste ground die. By providing a positioning shape forming portion for forming the shape into the rough shape, a forging die capable of easily and reliably positioning the billet and / or the rough shape with an appropriate volume of material is provided.

According to the first aspect of the present invention, the billet and the like can be easily and reliably positioned with a simple configuration in which a positioning shape that can be positioned with respect to the mold of the next process is formed into a billet or a rough shape material in the previous process. It is possible to provide a die forging method that can be performed.
According to the second aspect of the present invention, it is easy with a simple configuration in which a positioning shape molding portion for molding a positioning shape that can be positioned with respect to the die in the next process into a billet or a rough shape is provided in the mold in the previous process. In addition, a forging die capable of positioning billets and the like reliably and reliably can be provided.

An embodiment of the present invention will be described in detail with reference to FIGS. 1 to 3 by a case where a deformed part having a cross section such as a crankshaft which is one of automobile parts is subjected to hot die forging. In the drawings, the same reference numerals are given to the same or corresponding parts.
The die forging method of the present invention is roughly divided into a crushing step (S3) for flatly crushing the billet W1, a wasteland step (S4) for preliminarily molding the crushed billet W1 with a rough die 2 and a rough shape material, A finishing step (S5) for finishing the rough shaped material into a predetermined shape with a finishing die, and forming a positioning shape W1a that can be positioned with respect to the waste mold 2 into the billet W1 in the crushing step (S3). And / or a positioning shape that can be positioned with respect to the finishing die in the rough land step (S4) is formed into a rough shape material.
Further, the forging die of the present invention is roughly finished by a crushing die 1 that flatly crushes the billet W1, a rough die 2 that preliminarily molds the crushed billet W1 into a rough shape, and finishes the rough shape into a predetermined shape. The positioning die 15 is provided with a positioning shape forming portion 15 for forming a positioning shape W1a that can be positioned with respect to the rough ground die 2 into the billet W1 and / or the rough ground die 2 is finished with the finishing die. A positioning shape forming portion is provided for forming a positioning shape that can be positioned with respect to the mold into a rough shape.

  As shown in FIG. 1, in this embodiment, the material is cut into an appropriate length to form a billet W1, heated to a predetermined temperature, and a crushing process, a wasteland process, and a finishing process are sequentially performed. Trim burr and inspect.

  As shown in FIGS. 2 and 3 (a) and 3 (b), the crushing mold 1 is composed of an upper mold 10 and a lower mold 11 that are relatively close to and far from each other. A support base 13 is provided so as to be movable up and down, and an elastic body 14 such as a spring that biases the support base 13 to be raised is provided below the support base 13. Both support bases 13 and 13 are provided with recessed support portions 13a for supporting the end portions of the billet W1. Further, on the upper surface of the lower mold main body 12, there is a convex portion 15 as a positioning shape forming portion for forming a positioning shape W1a corresponding to the protruding portion 22 (see FIG. 3C) of the waste mold 2. Is provided. The lower surface of the upper mold 10 is appropriately formed according to the shape of the billet W <b> 1 sent to the wasteland mold 2, for example, a flat shape or a concave groove. In FIG. 2, the positions of the upper mold 10 and the lower mold 11 are shown to be shifted in order to explain the configurations of the upper mold 10 and the lower mold 11, but the upper mold 10 and the lower mold 11 are shown in FIGS. 3 (a) and 3 (b). Are arranged opposite to each other.

  3A, both ends of the billet W1 are supported by the support portion 13a of the support 13 of the lower mold 11, and the upper mold 10 is moved downward relative to the lower mold 11 to perform the crushing process. Then, the billet W1 is pressed by the upper mold 10 and the support base 13 supporting the billet W1 is lowered against the bias of the elastic body 14, and the billet W1 is lowered as shown in FIG. A concave portion W1a serving as a positioning shape is formed on the lower surface of the lower mold body 12 corresponding to the protruding portion 22 of the waste ground mold 2 by the convex portion 15 provided on the upper surface of the lower mold body 12. The recess W1a constitutes a positioning shape for positioning the billet W1 with respect to the waste land mold 2. In addition, the convex part 15 provided in the lower mold | type main body 12 is predetermined height so that the recessed part W1a of the grade which can be engaged with the part 22 which the rough ground mold 2 protrudes can be formed in billet W1, and , Slightly larger than the protruding portion 22. Moreover, the convex part 15 provided in the lower mold | type main body 12 is unevenly distributed in the one end side so that billet W1 may contact | abut to a positioning part with respect to the rough mold 2 like the prior art (refer FIG.4 (c)). 3 (c), the billet W1 can be positioned at the center of the wasteland mold 2 so as to correspond to the portion 22 protruding at an appropriate position. Yes. The shape of the convex portion 15 can be appropriately formed according to the protruding portion 22 of the waste land mold 2 used for positioning the billet W1.

  The billet W1 in which the concave portion W1a as the positioning shape is formed in the crushing process which is the previous process is then moved to the wasteland mold 2 for performing the wasteland process which is the subsequent process as shown in FIG. The concave portion W1a is positioned by being engaged with the protruding portion 22 of the lower mold 21 of the waste land mold 2. In this state, when a rough ground process is performed in which the upper mold 20 of the waste land mold 2 is lowered relative to the lower mold 21 and pressed, the billet W1 is held at an appropriate position without moving and set to an appropriate volume. The material of the billet W1 thus flowed according to the impression of the rough ground mold 2 is plastically deformed to form a rough shaped material having a predetermined shape.

  In this embodiment, the case has been described where the recessed portion W1a of the billet W1 is engaged with the protruding portion 22 of the lower mold 21 of the wasteland mold 2. However, the present invention is limited to this embodiment. The convex portion of the billet W1 is formed so as to correspond to the concave portion 23 of the waste ground mold 2, and the convex portion of the billet W1 is positioned by engaging with the concave portion 23 of the rough ground mold 2. You can also.

  Further, if necessary, the rough ground mold 2 is also roughened in the previous process so that a part that engages with the finishing mold is formed when the rough shape material is sent to the finishing mold and positioned in the finishing process, which is a subsequent process. A portion for forming a positioning shape on the material can be provided, and the positioning shape can be formed on the rough material in the roughing step. Further, the wasteland process (S4) and the finishing process (S5) can be configured by a plurality of subdivided processes.

  In the present invention, it is not necessary to provide a positioning part for unevenly contacting the billet W1 as in the prior art or to provide a groove-like holding part for holding in the radial direction. Since the volume can be set, there is no waste of material, and wear of a forging die such as a rough die can be reduced, so that the die life can be extended.

It is the block diagram shown in order to demonstrate an example of all the processes of the die forge forming method of this invention. It is a perspective view for demonstrating the crush type | mold used by the crushing process of this invention. A state in which the billet is arranged in the crushing mold in the crushing process which is the pre-process of the present invention (a), the positioning shape is formed in the billet (b), and the billet positioning shape is engaged with the wasteland mold in the subsequent process (c It is sectional drawing for demonstrating. In order to explain the prior art, a front view of a prepared billet (a), a front view of a billet crushed with a crushing mold (b), and a cross-section with a crushed billet arranged in a wasteland mold It is a figure (c). It is a perspective view of the conventional wasteland type | mold. It is a partial expanded sectional view for demonstrating the state which contact | abutted and positioned the end surface of the billet in the conventional waste-ground type positioning part. It is a partial expanded sectional view for demonstrating the state which hold | maintained the billet in the conventional waste-ground type groove-shaped holding part.

Explanation of symbols

W1: Billet, W1a: Concave part (positioning shape), 1: Crushing type, 2: Wasteland type, 11: Lower type, 22: Projected part

Claims (2)

Die forging that performs a crushing process for flattening the billet, a roughing process in which the crushed billet is preformed with a rough mold to form a rough shape, and a finishing process in which the rough shape is finished into a predetermined shape with a finishing die. A molding method,
A die forging method characterized by forming a positioning shape that can be positioned with respect to a die in the next step into a billet or a rough shape material in the previous step. A forging die comprising: a crushing die for flatly crushing a billet; a rough die for preliminarily forming a crushed billet to form a rough shape; and a finishing die for finishing the rough shape material into a predetermined shape.
A forging die characterized in that a positioning shape forming part for forming a positioning shape that can be positioned with respect to a die in the next step into a billet or a rough shaped material is provided in the die in the previous step.

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